enic: misc cleanup items:

Clarrify reading PBA has no side-effect (clearing).
Add missing GPL license text.

Signed-off-by: Scott Feldman <scofeldm@cisco.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/enic/vnic_intr.h b/drivers/net/enic/vnic_intr.h
index ccc4081..ce633a5 100644
--- a/drivers/net/enic/vnic_intr.h
+++ b/drivers/net/enic/vnic_intr.h
@@ -78,7 +78,7 @@
 
 static inline u32 vnic_intr_legacy_pba(u32 __iomem *legacy_pba)
 {
-	/* get and ack interrupt in one read (clear-and-ack-on-read) */
+	/* read PBA without clearing */
 	return ioread32(legacy_pba);
 }